Taking Thyroid Medications: Everything You Need to Know

Kinds of Thyroid Drugs

One of the most prescribed drugs in the United States has been Synthroid.  Hypothyroidism can be treated using three types of drugs: T4 drugs such as Synthroid, Levoxyl, Levothyroxine and Tirosint, T3 drugs such as Cytomel, and T4/T3 combination drugs such as Armour, Nature-Throid, and WP Thyroid. Individuals afflicted with Hashimoto’s thyroiditis may have impaired conversion of levothyroxine to liothyronine resulting in a more metabolically active thyroid hormone which can manifest as thyroid symptoms such as weight gain, fatigue, depression, and hair loss, despite being on treatment.

Drug Switching

Switching between different brands or generic thyroid drugs will probably result in variations of actual dosage as compared to your previous drug, which was already adjusted by your healthcare professional.  Your thyroid should be retested 4-8 weeks after switching from one brand of drug, or the dose must be readjusted periodically until the right amount is achieved.

Interactions with other drugs

Thyroid drugs are infamous for their interactions with other drugs, resulting in changes in their effectiveness and toxicity profiles. Consult with your healthcare professional before taking any other drugs to prevent such a scenario from happening.

Treatment Monitoring

Thyroid drugs are dosed in micrograms due to their narrow therapeutic index. Very slight variations in doses can result in unusual symptoms during treatment.  Rapid or irregular heartbeat, chest pain, irritability, nervousness, insomnia, weight loss, diarrhea, excessive sweating, hair loss, or fatigue have been determined as common symptoms of such variations. Consequences of over-or-under treatment can be prevented by careful dosage titration.  TSH, Free T3 and Free T4 should be monitored to track your reaction to the drugs. Your healthcare professional will be the one responsible to interpret your results and adjust your dose accordingly.

Addison's disease

You should always be tested for Addison’s disease before you start treatment with thyroid hormones.  This is in order to prevent a possibly life-threatening situation by having an increased clearance of glucocorticoids when thyroid drugs are given to individuals with untreated Addison’s disease.

Pregnancy

Thyroid drugs have been deemed safe for use during pregnancy.  Being dosed properly can actually aid in the reproductive process of females as well as prevent any problems during pregnancy such as miscarriages.  Consult with your healthcare professional if you get pregnant while taking thyroid drugs.  Your dose will increase due to the increased demands of thyroid hormones during pregnancy.

Drug Absorption

The absorption of thyroid drugs can be affected by food, other medications and supplements. Also, intestinal conditions like untreated celiac disease, lactose intolerance, malabsorption and infections can prevent optimal absorption of thyroid hormones.

Prognosis

Thyroid drugs are like anti-hypertensive drugs which generally must be taken for the rest of your life.  Spontaneous remissions have only been reported in a fifth of the total cases.  Thyroid function examinations should be performed at least every 6-12 months to monitor your thyroid hormone levels.

Other Factors

The most common underlying cause of thyroid disease is due to autoimmune conditions such as Hashimoto’s and Graves’ disease.The immune system attacks the thyroid gland due to false recognition of the thyroid as being a foreign or unnecessary object in the body. Autoimmunity still persists even after treatment with surgery or radiation.  The risk of having new autoimmune disorders such as Lupus, Rheumatoid arthritis and others diseases are increased if the underlying cause of the immune imbalance is left untreated. A combination of adrenal dysfunction, food sensitivities, nutrient deficiencies, impaired gut function, infections and toxins that lead to the development of autoimmune disease, have been reported as the primary causes of autoimmune diseases.

Related:Prevention and Treatment of Thyroid Disorders

Side Effects of Levothyroxine You Need to Know

Levothyroxine is a drug used to treat a lazy thyroid or hypothyroidism. While it is usually well accepted by the body, there is a risk for developing side effects of levothyroxine, such as allergic reactions if the drug is not taken properly. This drug contains a synthetically produced replacement for the thyroid hormone which can supplant the body's natural stores. Levothyroxine is prescribed when the thyroid has become impaired due to surgery, radiation, other drugs, or in the event that the thyroid must be detached.

Levothyroxine is anticipated to be used together with other forms of treatment including diet and exercise to sustain the fittest levels of thyroid function possible. This drug cannot be used to stimulate weight loss or infertility, unless these issues correlate from poor thyroid function.Taking levothyroxine combined with diet pills can cause perilous and potentially fatal side effects.

General Side Effects of Levothyroxine

In general, levothyroxine is well accepted in patients.  Most side effects originate from overusing the drug or using it erroneously.  Follow all instructions from your healthcare professional when using levothyroxine and inquire about anything you do not understand.  Common side effects of levothyroxine include heat intolerance, anxiety, increased appetite, weight loss, insomnia, diarrhea, palpitations, tachycardia, hypertension, angina, increased bowel frequency and menstrual irregularities.  These side effects classically appear several weeks after starting your prescription.

Cardiovascular Effects

Cardiovascular symptoms including angina, tachycardia, palpitations and hypertension have been reported in clinical trials when testing levothyroxine.  Patients already experiencing an underlying cardiovascular condition or disorder including heart disease or decreased cardiovascular function were significantly more likely to develop such side effects.Those with enhanced left ventricular systolic function and increased left ventricular mass index are also at high risk for developing cardiovascular side effects while using this drug.

Endocrine Problems

Adrenal cortical insufficiency or an increased presence of diabetes symptoms may occur when taking this drug.Those who are already at risk for having such conditions should consult with their healthcare professional about any potential risk before starting regular doses of levothyroxine.

Nervous System Effects

Neurological side effects to levothyroxine are erratic.Seizures have been reported during the initiation of therapy, but these usually regress after a few months.  Muscle weakness or hyperactivity leading to crankiness or unexplained irritability, have been reported in some patients taking levothyroxine.

Dermatologic Problems

Mild hair loss is usually observed when using levothyroxine. This side effect is not hazardous and typically halts after the body becomes acclimated to altered hormone levels. Temporary dermatologic effect has also been reported in the early months of using the drug.

Musculoskeletal Effects

An increased risk for osteoporosis has been reported in the prolonged use of this drug, particularly in those that are already at risk for developing the condition. The rates of femur fractures are greater in those using thyroid therapies than those who do not, especially in women. Reported by patients, is the feeling as though bones are more brittle, or are more prone to injury after using levothyroxine for long periods of time.